1. Field of the Invention
The present invention is in the field of construction and pertains particularly to methods and apparatus for supporting fixtures on a membrane roof.
2. Discussion of the State of the Art
In the field of construction, particularly roofing, membrane roofing as it is known in the art is becoming a staple for certain roof systems that formerly would be covered in asphalt and or roof tar. Membrane roofing panels are typically available in sheets or rolls that may be cut to length and that may be secured to an unfinished roof surface, and heat welded together to form a unitary membrane.
Although there are a variety of membrane roofing materials available, more common compositions include Polyvinyl Chloride (PVC), Ketone Ethylene Ester (KEE), Chloro-Sulfonated Polyethlene (CSPE), Ethylene Propylene Diene Monomer (EPDM) and Thermoplastic PolyOlefin (TPO). Membrane roofing sheets may be mechanically fastened through the membrane with a screw, pin type fastener or other mechanical means un-finished roof with an overlapping edge of an adjacent sheet heat welded over the fastened line to cover and seal the fastener. Membrane roofs can also be adhered using a variety of adhesives by applying adhesive to the existing roof substrate, insulation, fire proof roof board or unfinished roof substrate. The exposed seams of the membrane are then heat welded to create a solid membrane out of the panels or rolls. Heat welding the panels together involves a surface-to-surface heating and fusion of the interfacing surfaces of adjacent panels or sheets, requiring a certain minimum temperature.
Membrane panels or sheets may be custom fabricated and may be offered in standard sizes. The material resiliency including flexibility may be designed into the product through varying the percentage of certain materials in the composite such as different percentages of rubber added to the composite.
Installing fixtures such as pipe brackets, solar panels, roof vents, air-conditioners, and other like accessories can be problematic after a membrane roof is installed, in that support structures designed to hold the fixtures in place are conventionally nailed or otherwise fastened to the roof over the membrane material, penetrating the membrane material at each anchor point. Although the penetrations may be small, nonetheless, roofing mastic, caulking, sealants, or a similar semi-viscous sealer is applied over the penetrations to seal them ensuring a leak proof or watertight roof system.
It has occurred to the inventor that such penetrations, although minor, have a collective negative effect on the long-term viability of the roofing system in protection against leakage. For example roofing mastic, caulking, sealants, roof putty or other after-market sealers do not last as long as the membrane materials of the roof systems and therefore periodic reapplication of such sealing products is often required to preserve the integrity of the system, or leaks are sure to occur. Many roof manufacturers provide leak free warrantees that cover labor and materials up to 30 years. Penetrations directly into the roof membrane can in certain instances void these warrantees.
Therefore, what is clearly needed is an apparatus for supporting fixtures on a membrane roof that altogether eliminates the need for penetrating the membrane roofing material.